Daddy's Little Demon
by goodbyehollywood
Summary: In which Sebastian Morgenstern finds himself stuck fathering a bouncing baby demon, trying desperately to keep a very angry Clary from escaping, and having to convince everyone that red gear is not worse than wearing neon-colored Crocs. Rated M for language.
1. Part 1

**WARNING: This is supposed to be a** **humorous** **, light-hearted story and should in no way be taken seriously. This fanfic is completely pointless and is not meaningful or moving in the slightest. If you like cute babies and making fun of Sebastian/Jonathan, please enjoy. If not...I don't really know what you're still doing here, to be honest.**

 **Takes place after CoLS and before CoHF.**

"My Lord."

With a growl, Sebastian whipped off his sunglasses and snapped, "What is it, Amatis? Can't you see I'm trying to tan?"

Amatis bowed her head slightly. "My apologies for interrupting you, Master, but I come bearing news."

"Spit it out, then." He eyed the bundle in her arms warily. "What is that?"

"Precisely what I've come to speak to you about, my Lord." Amatis adjusted the bundle so that it rested in one arm; she brushed corner of the wool blanket away, revealing soft pink cheeks, a button nose, and a fringe of white-blond hair.

A look of horror crossed Sebastian's face. "Amatis, what is _that?"_

"A child, my Lord," Amatis said slowly. "Your child."

" _My_ child?" Sebastian hissed. "Impossible."

"Quite the opposite, my Lord. She looks just like you."

"Where did this thing come from?" Sebastian demanded. "Where is its mother?"

"She left, my Lord."

"She _left?_ She came, dropped this _thing_ off, and you just let her leave? What the hell is wrong with you?"

Amatis glanced down at the sleeping baby. "I assume you're not going to keep her then, my Lord?"

"Keep her?" Sebastian curled his lip. "Amatis, I am the Lord of the Endarkened. What use could I have for a _child?"_

"If you do not wish to keep her, what shall we do with her?"

"Kill it," Sebastian said nonchalantly, flipping his shades back on. "Poison it, burn it, cut its throat—I don't care how, so long as it's dead before sundown."

Amatis hesitated. "My Lord, are you quite sure you don't want to-"

"Amatis, there's no way to be sure that she's even _mine."_ Sebastian sniffed, shooting the bundle a cold glance. "Who was her mother, anyways?"

"A woman."

Sebastian growled, "I assumed that much, Amatis. _Who_ was she?"

"That I do not know, my Lord. She was a Nephilim who came by this morning. She did not give us her name."

"Nephilim, you say?" Sebastian rubbed his chin, leaning back into his lawn chair. "I've lured countless Shadowhunter women into my bed. How could I possibly remember which woman you're talking about?"

Amatis gazed down at the child, who'd begun to stir. "Are you quite sure you want her killed, my Lord? She does look an awful lot like you."

"I'll be the judge of that!" Sebastian snapped, leaping to his feet. "Hand it over."

Amatis gently placed the stirring baby into Sebastian's open arms. "Be careful with her, my Lord. She's hardly more than a newborn."

Sebastian took the baby and held her up by her armpits. The babe's big black eyes fluttered open, framed by long white lashes. At the sight of her scowling father, the baby's face split into a gummy pink grin.

"It's hideous," Sebastian said monotonously. "This _creature_ could not possibly share my blood."

"She has your nose," Amatis said fondly. "And your eyes."

"I suppose it does." Sebastian examined the baby with narrowed black eyes. "Amatis, what am I supposed to do with it?"

"Does this mean you're keeping her, my Lord?"

"I said no such thing," Sebastian said quickly. "I am only considering letting it live."

"You could drop her off at an orphanage," Amatis suggested. "Or a nursing home. Elderly people adore babies. She'll be well cared for."

Sebastian considered this. His half-demon daughter—at least, he assumed that's what she was—raised by a bunch of elderly humans who smelled of soap and raisins? The mere thought made his lip curl.

"Blasphemy!" Sebastian snapped, tossing the infant over his shoulder. The child giggled gleefully. "I'll not have my own flesh and blood grow up surrounded by withering prunes."

Amatis's face lit up. "Will you keep her?"

"Yes," Sebastian declared. "Once she's grown, she'll make a powerful weapon. I won't make the same mistake that Jocelyn did with Clarissa."

"Very good, my Lord. What shall you call her?"

Sebastian froze. "What?"

"Her mother didn't give her a name. What will you call her?"

Sebastian pondered this. What _would_ he call her? Naming her after either of his parents was certainly out of the question; he hated them both. He'd never much liked the name 'Clarissa' either, mainly for its lack of sophisticated grace. _Seraphina?_ Sebastian frowned. _Adele, perhaps?_

A thought occurred to him, and he broke into a wide grin. Lilith. Lilith Adele, after the only two women he'd ever loved. It was perfect.

"Lilith Adele Morgenstern," Sebastian purred, holding the child up in front of him. "What do you think, Amatis?"

She smiled wide. "A wonderful choice, my Lord."

"Lilith Adele," Sebastian repeated. He adjusted the little demon so that she rested cradled in the crook of his arm; Lilith yawned and blinked sleepily, fluttering her snow-white lashes. She snuggled into his chest, purring at the warmth he emitted. Sebastian felt a strange sensation stir deep in his chest, and his cheeks flushed pink.

"My Lord?"

Sebastian jumped. "Y-yes? What is it?"

"The portal is open, my Lord. We await your command."

"Portal. Of course," Sebastian cleared his throat. "To Edom."

Amatis bowed her head. "Lead the way, my Lord."

Sebastian gave a stiff nod, adjusted Lilith in his arms, and started back towards what remained of the Los Angeles Institute. _Come, little demon._ A smile played on Sebastian's lips. _We're going home._


	2. Part 2

**And here's Part 2. I don't really want to call them chapters, since this is gonna be a relatively short project; sorry folks.**

 **There's still more to come, though! Remember to R &R!**

* * *

 _Shit, that hurt._

Sebastian let out a pained, barking laugh, knocking Clary to the ground with a powerful swing of his arm. The tiny redhead landed with a muffled _thud._ She groaned, cradling her bruised cheekbone.

"Don't test me, Clarissa," Sebastian said softly, as he wiped the blood from his split lip. "You know I'm not a patient man."

"The only thing I know," Clary hissed, breathless, "is that one, you're a fucking _psycho—"_

"Language, little sister—"

"—and two, nobody wins with a head butt." She rubbed the sore spot on her head. "God _damn,_ that hurts like a bitch."

"Language!" Sebastian snapped, again. "I'll not have my sister cursing like a common sailor."

Clary smiled sweetly. "Right. Sorry, big brother." She flipped him off.

Sebastian sniffed disdainfully. "I see I'll have to teach you some manners," he said observantly. "No matter. I think I'll enjoy this." Sebastian flashed a wicked grin and shrugged off his jacket.

Clary raised her fists and leapt into a fighting stance. "Come at me, mofo. I can go all day!"

"Good to know," Sebastian flexed his lean, rune-adorned muscles. "I do love a woman with stamina."

"Keep being creepy and I'll punch your shriveled little balls in."

Sebastian gaped, bearing a striking resemblance to a sea bass. " _Shriveled?_ How dare you!"

"Yeah," Clary smirked. "Like two wrinkly little raisins. With a limp French fry in the middle."

Sebastian snarled, livid. "You will eat your words, little sister. I'll make sure of it." He bared his teeth in a vile smirk. "Right after you drink from the Cup."

Clary's eyes widened. "Oh _hell_ no."

She took off running. Sebastian let out a long sigh. _The chase was fun at first. Now it's just getting tedious._ He sprinted after her.

His palace in Edom was a maze, composed of various winding hallways and dark corridors-perfect for a tiny thing like Clary to lurk about and hide in. Sebastian paused and listened for the sound of her light footsteps. His ears caught the sound of Clary flitting about somewhere to the west. He followed the soft pitter-patter of her small feet, making sure to tread quietly. _A Soundless rune would be good right about now,_ he thought exasperatedly.

"Clarissa?"

The sound of her footsteps came to an abrupt halt. Sebastian smirked. "Clarissa," he called again. "Where are you? Come out and play, little sis. I'm getting bored."

"Screw you."

Sebastian laughed, "Believe me, I've dreamt of nothing more since the day I met you." He looked up to find Clarissa clinging to the chandelier above his head. She stuck her tongue out at him.

"Piss off, you incestous freak."

"Come down from there, Clarissa." Sebastian's voice turned stern. "You're going to fall."

"Yeah, but not before I die of boredom from listening to you talk. Are you really incapable of shutting up for more than five seconds?"

Sebastian squinted at her. "How the hell did you even get up there?"

"A magician never reveals her secrets."

"Clarissa."

"Sebastard."

He grit his teeth. "Very mature, Clarissa."

"Thank you, Shitbastian."

"Come down."

"Hell no."

Sebastian's lip twitched. "Fine," he growled. "I suppose that if you don't want to come down, I'll just have to come up." He approached one of the pillars supporting the ceiling and started to climb.

"What? No!" Clary removed one of her sneakers and chucked it at his head. "Get away, freak!"

The shoe hit Sebastian square in the forehead; he cursed loudly. " _Clarissa!"_

"You can't come up here," Clary snapped, sliding off her other shoe. "Your fat ass is gonna make us both fall!"

"Then come down, or I swear I will-"

"You'll what, lard-ass? Sit on me until I beg for mercy?"

Sebastian opened his mouth to respond, but the sharp cry of an infant cut him off. _Lilith?_ Sebastian looked down to find Amatis standing by the pillar, cradling a wailing Lilith in her arms. "My Lord?"

Shooting a smug Clarissa a deadly glare, Sebastian pushed off the pillar and landed on his feet next to Amatis. "What is it, Amatis?"

"The princess will not stop crying. We don't know why."

Sebastian narrowed his eyes at the babe. "And just what would _I_ know about raising a child? One of my parents abandoned me. The other whipped me until my back was raw, regularly. Have you tried feeding it?"

"Yes, my Lord."

"Changing her diaper?"

"Yes, my Lord."

"Putting her to sleep?"

"She just woke up, my Lord."

Lilith let out another earsplitting cry; Sebastian winced.

"Would you like to try holding her, my Lord?"

"And what good would that do?"

"You're her father. Perhaps she craves your affection."

 _Craves my affection?_ Sebastian felt his ears go pink. "F-fine. Hand her over."

Amatis placed the whimpering child in his outstretched arms, and almost instantly, Lilith quieted. She broke into a toothless pink grin and giggled, waving her chubby little arms. Sebastian all but melted. _Now I see why people are so fond of these little horrors,_ he thought. _Ugly and annoying as they are, they're preprogrammed to love you._ He smiled a bit. _I could get used to this._

"What the hell is that?"

Sebastian looked up and hissed, "Clarissa, do not use such language in the presence of a princess!"

"Princess?" Clary demanded. "Jonathan, what the hell did you do?"

He flinched at the use of his real name, but then quickly recovered his cool mask. He smirked. "I had unprotected sex, apparently."

Clary's eyes widened. "You…"

"That's right. Clarissa, say hello to your niece, Lilith Adele Morgenstern."


	3. Part 3

**Part 3! Enjoy!**

 **Please note, though, that this is NOT a Clabastian fic. I'm not cool with incest. I just REALLY love making fun of Sebastian.**

"I'm calling Child Protective Services."

Sebastian raised an eyebrow as he bounced a happy Lilith in his lap. "Why?"

Clary hissed, "Because, demon or not, no child should be subject to having _you_ as a father. You're worse than Valentine."

"Really?"

"Yes," Clary growled. "Valentine was a monster. You're...worse. So much worse."

"How so?"

"Well, for one, you tried to rape me."

Sebastian scoffed. "You were a lot more fun to be around while you were unconscious."

"And you were a lot more fun to be around when you were dead, but I guess life is just full of disappointments."

"Harsh," Sebastian smirked. "Come on now, Clary. Won't you at least try to get along with me? You know Lilith is going to get lonely eventually. We'll have to make her some _playmates-"_

"By the Angel," Clary raked her fingers through her hair. "Does it seriously not bother you that those 'playmates' would be both your daughter's cousins _and_ siblings?"

"Not really."

"Hasn't anyone ever told you that Cersei and Jaime's relationship is not supposed to be idealized?"

Sebastian frowned. "I have no idea who those people are."

"They're brother and sister," Clary snapped. "Much like you and I, dumbass. Brothers and sisters are _not supposed to hook up._ How do you not understand that?"

"Things are different for us, Clarissa. We're not even the same species. How do _you_ not understand _that?"_

Clary crossed her arms. "Then in that case, I suppose you'd be happy if Lilith started doing the nasty with one of her cousin-siblings?"

Sebastian bristled. "My daughter will not be doing _anything_ with _anyone,_ ever." He felt a strange protectiveness posses him; the mere thought of some vulgar-minded boy going anywhere near his daughter made his fists clench.

Clary snarled, "You're a hypocrite."

"How so?"

"You've slept around with probably more women than you can remember, _and_ you've made it crystal clear time and time again what you want to do to _me,_ but the thought of your daughter following in your footsteps repulses you because she was born a _girl."_

"Yes," Sebastian said. "I am a man, Clarissa. I know what men want, what men think—we're vile creatures, little sister. Forgive me if I want to protect my daughter from the likes of us."

"Yeah? Well why can't you protect me from the likes of you, too?"

"You've nothing to fear from me, Clarissa." Sebastian smirked. "My intentions are honorable. We're going to save the Morgenstern bloodline—"

"—ew _, so_ not happening—"

"—and maybe do some kinky stuff in the process, just for fun." He covered Lilith's tiny ears at that last part, grinning wickedly.

"You're gross." Clary glanced out the window at the barren wastelands of Edom. "Hey, Jace? Any time would be great now, sweetie."

 **Meanwhile at the Institute…**

"Sweet Raziel, please let this work…" Jace carefully reached for the ripe yellow mango sitting on the table. He picked it up with no problem. Just as he was about to start celebrating, however, the fruit burst into flames and then dissolved into a pile of ash. Heartbroken, Jace sucked in a deep breath and whispered, " _What's the point in living?"_

 **Back in Edom…**

Sebastian set Lilith in her crib; she was swaddled in the same wooly blanket she'd been delivered in, sleeping peacefully. The Lord of the Endarkened smiled down at her. Warmth fluttered in his chest. _Sweet dreams, my little demon._

He left the room, making sure to close the door quietly as he departed. Clary was still sitting in the ornate grand room when he returned, glaring out the window and tapping her fingers on the chair's armrest. Scowling as she was, she looked lovely in the dim light of the lit fireplace. Sebastian felt something stir deep in his abdomen. He bit his lip and flashed a cunning smile.

"Sister."

"Shithead."

Sebastian's mouth twitched, but he let the insult slide. "I'm bored."

"Boo-fucking-hoo."

"Come on, Clary," Sebastian drawled, letting the door click shut behind him. "Don't be like that."

His sister tensed. "Jonathan…"

"Let's have some fun, shall we?" Sebastian purred. "Some quality brother-sister bonding time. Doesn't that sound nice?"

Clary stood up. "Keep on being a creep and I swear, I will rip your nutsack off."

He flicked the top button of his shirt open. "I _love_ it when you talk dirty to me, little sister," Sebastian murmured, taking a languid step towards her.

"Rip it," Clary said again. "Like, _clean off._ You think I'm kidding?"

"No," Sebastian shook his head, popping yet another button open. "I don't. I know you'll try—and that's what's going to make this fun." He smirked. "Now, let's get to work on those sibling-cousins, shall we?"


	4. Part 4

**Part 4 for you all! To be honest, I'm** **actually** **surprised that people are actually liking this story. This was honestly just a stupid idea I came up with while shopping at T.J. Max one day, but I'm glad you guys are entertained by it. Enjoy! R &R!**

 **(PS, we're seeing some of the other characters in the next chapter!)**

Sebastian expected Clary to struggle, but he hadn't expected her to actually hit him—and certainly not with a chair.

He didn't know how long he'd been out. When he finally came to, his sister was gone and his clothes were disheveled. Sebastian sat up and fixed his rumpled clothing. The way his pockets were turned out made him realize something: he'd been robbed.

He felt around for the familiar feel of a small cylinder pressed against his thigh, but found nothing. Sebastian gulped. Clary had taken his stele.

 _Not good. Definitely_ not _good._

The Lord of the Endarkened scrambled to his feet and dashed out of the grand room. He paused to listen for any hint of commotion; a high-pitched giggle sounded from the direction of Lilith's room. Sebastian turned on his heel and sprinted towards the source of the noise.

The nursery door had been left ajar. Sebastian kicked it open and stepped inside to find Clary standing in front of a Portal, holding a wriggling bundle in her arms.

"Shush," Clary scolded her lightly. "You'll give us away!"

Sebastian snarled, breathless, " _Too late."_

Clary whipped around. "Oh, hey Shithead. I was just on my way out. See ya."

She stepped through the Portal, and was gone before Sebastian could blink.

 _Fuck._

Sebastian lunged at the Portal, but it vanished and he ended up running face-first into the wall. A searing pain spread through his face, and something wet and warm started oozing from his nose. "Shit," Sebastian gasped. He clutched his bloody nose and hobbled out of the nursery, screaming, "Amatis! Get your Endarkened ass over here _now!"_

"I am here, Master."

Sebastian whirled around to find the older woman standing only a few feet away. He shuddered; he hadn't even heard her move! _These Endarkened turned out a little creepier than I intended._

"My sister has escaped," Sebastian hissed. "She's taken Lilith. Prepare for a retrieval mission. We're going to New York."

"Yes, Master." Amatis turned to walk away, but then paused. "Before I forget, Laramie Hollyberry told me he wishes to speak with you about our uniform budget, Master."

"Amatis," Sebastian growled slowly. "Does this _really_ seem like a good time to you?"

"We don't have any money left, Master. We can't afford to buy any more gear."

"What?" Sebastian's eyes widened. "What do you mean, we don't have any money? We have plenty of money!"

"The designer you hired sent us a very angry fire-message saying that our check bounced. She's demanding payment in cash."

"So? Just kill her and steal the gear."

"Master, would it not just be easier to use the black gear we already have?"

"Absolutely not!" Sebastian snarled. "Every evil army needs to have a _thing,_ Amatis. Red gear is our thing. It's what makes us identifiable."

Amatis glanced down at her own gear. "It's such an unflattering color," she muttered.

" _What was that?"_

"Nothing, Master. Shall I set up an appointment with Laramie at a later date?"

"Fine," Sebastian seethed. "Just hurry up and get ready to go. We're leaving in five."

"Very good, Master." Amatis turned and disappeared around the corner.

Sebastian let out an exasperated sigh. _Leading an army of brainwashed minions has turned out to be more work than I expected,_ he thought. _I should've just branded them with a new rune or something. Would've been_ way _cheaper._ He gritted his teeth. _Looks like I'm gonna have to go and beg that damn Seelie Queen for another loan._

He made his way out of the hallway and into the throne room; Amatis had gathered a group of his most competent Endarkened Shadowhunters unsurprisingly quickly. All of them stood in a perfect line, hands by their sides, staring blankly ahead. Sebastian backed into the hallway, slightly bothered. Sometimes, his creations scared even _him_ shitless.

Sebastian took Phaesphoros from where it leaned on his throne and slung it over his shoulder. "Are we ready?"

"Yes, Master." Amatis bowed her head.

One of the Endarkened raised his hand. Sebastian's brows knit. "What?"

"I have to go to the bathroom."

Sebastian sucked in a frustrated breath. "Why didn't you go earlier?"

"Because I didn't have to _go_ then!"

Sebastian's jaw clenched. "Then I guess you'll just have to hold it."

A second Endarkened piped up, "But I have to go too!"

"Me too!"

"And me!"

" _QUIET!"_ Sebastian roared. The hall fell silent. Taking in a trembling breath, Sebastian said quietly, "Who else needs to go?"

More than half of his army raised their hands. Sebastian clenched his fists. _You've got to be fucking kidding me._ "Fine," he hissed. "Go! But make it fast!"

The Endarkened streamed out of the room like a school of red-clad sardines, leaving only a pathetic gaggle of warriors standing awkwardly behind Amatis. For what seemed like a thousandth time that day, Sebastian sighed and pinched the bridge of his nose. _Lilith help me._


	5. Part 5

**Part 5! I'm having loads of fun writing this, guys, and I'm so glad people are actually liking it. Remember to R &R!**

"Guys! Guys, I'm back, I'm okay!"

Alec, Isabelle, and Jace glanced at the doorway where Clary stood with a tiny bundle in her arms. Alec raised an inquisitive eyebrow. "What?"

Clary's smile faded. "I'm back. Wasn't I gone for long?"

"Clary, you left to go to the bathroom like ten minutes ago." Isabelle tilted her head curiously as she eyed the bundle in Clary's arms. "What's that?"

"Wait a minute!" Clary cried. "You mean I got _knocked_ _out_ by my psycho demon brother and dragged into another _freaking_ dimension, and none of you even noticed?"

Jace froze. "Wait, what? Sebastian was here?"

"Yes! He _kidnapped_ me!"

Jace was up in a flash. "Where is he? I'll kill him—"

"Shut up and sit down, Angel Boy," Clary snapped. "He's not here. I managed to escape, no thanks to any of you."

"We're glad you're back and everything, Clary, but I believe we have yet to address the elephant in the room." Alec gestured at the bundle. "What is that?"

Clary brushed the corner of the wool blanket away from Lilith's face. "Well, it's kind of a long story…"

"You were gone for ten minutes. It can't be _that_ long."

Clary glared at him. "Fine. Everyone, say hello to my niece."

The room was quiet enough to hear a pin drop.

"Please tell me you're joking," Jace said. "Please tell me that you are not _actually_ holding the spawn of Sebastian-freaking-Morgenstern in your arms."

Clary glanced down at Lilith, who was making small whimpering noises as she struggled to get comfortable in her aunt's arms. Jocelyn had said that when Sebastian was a baby, he hadn't showed any real emotion. But this wasn't the case with Lilith. She smiled and laughed and cried like any normal baby. Even her father-given black eyes were alive and snapping with vibrant emotion.

"She doesn't seem like she's got demon blood," Clary said quietly. "I mean, just look at her. She's a normal baby."

Isabelle got up and came over to inspect the child. She narrowed her eyes. "She looks just like him."

"But she's not like him," Clary said. "My mother said that Sebastian didn't show any emotions when he was a baby. He didn't even cry. Lilith's not like that."

"By the Angel," Isabelle gave her an incredulous look. "He named her after a _demon?"_

"This is Sebastian we're talking about," Alec said dryly.

"What are you gonna do with her?" Isabelle questioned. "The Clave-"

"We are sure as hell not telling the Clave, or anyone outside this room, for that matter," Clary interrupted. "Except for Simon. And Magnus. And maybe my mom-"

"Clary," Alec said. "We can't keep this thing here."

"She's not a _thing,"_ Clary argued. "She's more Shadowhunter than demon. And besides, Sebastian turned out bad because Valentine raised him. Maybe if we were to take this little one in, she could grow up to be good."

"Wishful thinking," Jace shook his head. "But no. Clary, for all we know, this isn't even Sebastian's kid. It could be a demon in disguise."

"Then explain how I got her past the Institute's wards."

The hall fell silent. Alec spoke up, "Y'know, she's got a point."

Jace sniffed disdainfully. "Or she could be a spy."

"Jace, she's two months old."

"She's part demon. You don't know what she's capable of."

Clary rolled her eyes. "Well, I'm taking her home to my mother. She'll know what to do."

 _"_ _Over my dead body."_

"Oh for the love of-" Clary whirled around to snarl at Sebastian, who'd appeared in the doorway with a legion of Endarkened behind him. "Did you seriously follow me here all the way from your crappy knock-off demon Gard?"

Sebastian bared his teeth. "My Gard is not a knock-off. My Gard is better than your Gard."

Jace piped up, "Yeah, well my Gard is bigger than your Gard."

"I think most women would agree that my Gard is in fact the biggest and bestest Gard of them all."

"Okay," Alec said cautiously. "I think we've gotten off topic here."

"Silence, peasant," Sebastian snapped, pointing Phaesphoros at him.

Jace came to Alec's defense. "Hey! Nobody calls my _parabatai_ a peasant!"

Alec stood up a little taller.

"Except me!"

Alec deflated.

Sebastian appeared unimpressed. He casually flicked the tip of his blade. "Keep them away from me," he drawled lazily. "And fetch me my sister and my daughter."

"You're not gonna touch Clary!" Jace snarled, leaping up to stand in front of her. "You can take your demon kid back, though. Clary, give it to him."

Clary's eyes widened. "JACE."

He huffed. " _Fine._ You can't have either of them." He muttered something inaudible under his breath.

Sebastian snapped at his Dark warriors, "Quickly! Before the entire Clave comes running, you fools! We can't be here for long!"

The Endarkened surged forward. Jace faced the oncoming Shadowhunters fearlessly, until he realized that there were no weapons strapped to his belt. He gulped. "Well, shit."

"We're totally unarmed," Alec backed away from the charging horde.

"Plan B, then," Clary said.

Isabelle turned to her. "What's Plan B?"

Clary clutched a wailing Lilith to her chest and turned on her heel, calling over her shoulder, "FUCKING _RUN!"_


	6. Part 6

**Part 6! Thanks so much for all of the reviews! Keep 'em coming!**

"Alexander," Magnus said impatiently. "Get away from the window. You're scaring the pigeons."

"They could still be out there," Alec hissed. "Lurking. Waiting for us to let our guard down so they can attack."

"Alec, it'd be pretty hard to miss an army of Endarkened Shadowhunters marching through New York. I think we'll be okay," Clary remarked as she cradled a sleepy Lilith in her lap.

"I think not," Jace joined Alec in peeping outside the window. "Constant vigilance is key to avoiding ambushes."

"And decapitations," Alec added.

"And disembowelment," Jace finished.

Magnus, whose demeanor appeared dull and tired rather than glittery and cheeky, shot the _parabatai_ a glare and sighed. Considering the way things had ended between himself and Alec, he wasn't exactly in the mood to be hosting an unannounced Team Good meeting.

"So," the warlock said. "Is there a specific reason why you all decided to interrupt my Saturday with your Shadowhunter dramatics?"

"Dramatics?" Jace whirled around. "We were attacked by Sebastian and his Endarkened. I'd hardly call that _dramatics."_

"Sebastian Morgenstern was here?"

"Yes," Clary said. "He kidnapped me."

"For like two minutes," Isabelle said.

"He still kidnapped me," Clary snapped. "He took me back to his demon wasteland and tried to pull a Cersei-Jaime on me. Luckily I-"

Jace held up a hand, signaling for her to stop. "Wait, a _what?"_

"Never mind!" Clary hissed. "Magnus, I need you to examine this baby." She stood up and offered Magnus the drowsy babe; Lilith's eyelids were already drooping. Magnus's brows furrowed.

"What is this?"

"My niece."

"Your _niece?"_

"Yes, that's what I just said," Clary said rashly. "She's Sebastian's daughter. I need you to see if she's normal or not."

Magnus's cat eyes widened. "You've brought Sebastian Morgenstern's daughter into my apartment? What's the matter with you?"

"We had nowhere else to go," Isabelle said. "Sebastian's army overtook the Institute."

"And you couldn't be bothered to Portal into a Motel 6 or something?"

"No," Jace said lazily. "Why would we _pay_ for a room when we can stay at Hotel Magnus for free?"

Magnus let out a long sigh. "If I look at your demon baby, will you please leave? I would rather not have Morgenstern's army of mindless drones come knocking at my door this afternoon."

"Fine," Clary said, just as Jace was about to complain. "Now here." She offered up the bundle again.

Hesitantly, Magnus took the child and cradled her in the crook of one arm, using his free hand to brush a flicker of bluish magic over her tiny body. Lilith fidgeted, making little delighted noises at the sudden ticklish warmth.

"I do sense a trace of demon in her," Magnus said. "But not much. The majority of her feels human. Totally normal. The most I'd expect out of her are enhanced speed and strength, and possibly a knack for coming up with creative ways to torture her parents."

"So she _is_ normal," Clary concluded.

"Call it what you will, I really don't care." Magnus handed the child off to her once again, brushing himself off. "Now shoo. I have a very busy day ahead of me, if you all don't mind."

"Really?" Jace glanced around. "Looks like you've just been sitting here sulking all day. This place stinks of Chinese takeout and desperation."

Magnus flushed angrily.

* * *

 _Hello, Clarissa._

Sebastian, like a common creeper, lurked in the shadows of a dark alleyway, watching quietly as his sister and brother made their way towards the werewolf's house. Lucian Greymark, if he remembered correctly. The filthy dog that was currently keeping his mother wrapped around his pinkie finger.

And there, wrapped in Clary's arms like a little wool burrito, was his daughter. Sebastian's grip tightened on Phaesphoros. _You're going to regret crossing me, little sister._

"I'm telling you, Clary, it was sizing me up to see how many of its demonic children I would feed. I could see it in its eyes!"

"For the Angel's sake, Jace, the duck was after your pretzel, not you."

"That's what it wanted us to think," Jace hissed. "But I know better. I'm a _Herondale."_

 _Really? I couldn't tell,_ Sebastian thought with a roll of his eyes. He stepped out of the shadows and raised his blade, screaming, "Have at thee!"

"What the…" Jace glanced over his shoulder. "Oh, it's you. Here to get your ass kicked? Get behind me, Clary, I've got thi-"

"Oh no you don't, Herondale, this one is _mine."_ Clary placed Lilith in Jace's arms; the blond boy opened his mouth to object, but Clary ignored him. "Put 'em up, Sebastard!" She crouched into a fighting stance, fists raised.

"Ah, so my little sister desires a bit of close hand-to-hand combat? Very well." Sebastian sheathed the Morgenstern blade. "I am more than happy to oblige. Shall we- _oof!"_ Sebastian let out a low hiss of pain, doubling over to cup his injured area. "I wasn't _ready!"_

Clary nimbly leapt from foot to foot, circling him. "I promised you I would punch your balls in, didn't I, Shitbastian?"

"How dare you mock me so," Sebastian croaked, trying his best to sound intimidating. "I am Sebastian Morgenstern, Lord of the Endarkened, Son of-"

Clary landed a punch to his jaw, and then a kick to his abdomen. The blows didn't hurt Sebastian more than they unbalanced him, causing him to fall on his ass.

"Lord of the Endarkened my _toe,"_ Clary sneered. "I just knocked you on your ass!"

"You show him, honey!" Jace cheered. Lilith whimpered, reaching for the man she recognized as her father. Sebastian felt a pang of longing in his chest.

He stood up. Clary confidently took another swing, but her brother was ready. He caught her fist and squeezed, drawing a sharp squeal of pain from her throat.

"Clary, Clary, Clary," he shook his head. "Naughty girl. If I were you, I would stop this foolishness. You're already in enough trouble as it is. I'm still angry at you for running off like that."

"Bite me."

Sebastian chuckled. "In good time, little sister." He glared at Jace. "Hand over my daughter, Angel Boy."

"Sure," Jace said. "In exchange for my girlfriend."

"You are in no position to be making demands, my friend."

Jace opened his mouth to respond, but then the cold edge of a blade pressed against his throat, cutting him off. He gulped. "Shit."

"Release the princess, boy," Amatis commanded.

"Sure thing," Jace held Lilith out away from his body. "Take her."

Clary gaped. " _Jace!_ What the hell?"

"What? She's dying to go back to him anyways. Just look at her." Jace nodded at Lilith, whose little limbs were churning helplessly in the air as she tried in vain to get back to Sebastian.

The Lord of the Endarkened sniffled a bit. "Precious thing," he sighed. "Look at how much she loves me, Clarissa. Why can't you be more like her?"

Clary snorted. "You think she loves you now? Just wait 'til her teen years."

"Ah, of course. The older she gets, the more she'll adore me."

Clary rolled her eyes. "Oh yeah, _definitely_. Moron," she added quietly.

"Amatis, collect my daughter. We're going home." Keeping Clary in a headlock with one arm, Sebastian used the other to point threateningly at Jace. "Mark my words, Jace Herondale. I'll be back for you and all your worthless friends."

Amatis placed her hand on Sebastian's shoulder. He twisted his ring, and the group disappeared.

Jace pressed his lips into a hard line. "Well this is gonna be fun to explain to Jocelyn."


	7. Part 7

**Part 6! Enjoy!**

"My Lord, to put it simply...your bank account is empty. We have no funds."

Sebastian leaned forward in his throne. "We have _some_ funds."

"No," Laramie Hollyberry said stiffly, shaking the colorful beads of his abacus. "We have none. Zero. Zilch. _Nothing_. The Seelies have even seized my calculator, so I've been having to use an abacus like some sort of caveman!"

"We _must_ have _something!"_

"We have nothing. You spent your father's entire fortune on leather pants and eyeliner, remember? And the Seelie Queen's loans all go towards affording the rent for this knock-off Gard." Laramie gestured to the magnificent throne room around them.

"How dare you," Sebastian snapped. "I'll have you know, Larry, those loans were _hard earned._ The Seelie Queen is a very demanding woman."

"I'm sure she is. But that doesn't change the fact that we can't afford the rent this month, or any more red gear."

Sebastian bit his thumbnail, but quickly stopped when he remembered that Valentine used to beat him for nail-biting. He rubbed his chin. "What do you suggest, Laramie?"

"Perhaps it's time you found a job, Master."

"A job? No. _No._ Mundanes have jobs, Laramie, not _Lords of the Endarkened._ This _is_ my job."

"To be completely honest, Master, wreaking havoc upon the world is not exactly the most rewarding of occupations."

"We loot the Institutes, don't we?"

"Well," Laramie said flatly. "Yes, but we've been swamped with so much debt over these past few weeks that every time we raid an Institute, all of our spoils go towards repaying the angry demons and Downworlders you've swindled."

"Swindled is such a harsh word," Sebastian drawled. "I prefer the term 'outsmarted'. Don't you, little sister?" He turned to the gold and white throne beside him, where Clarissa sat wrapped in thick ropes. She flipped him off with some difficulty, as her hand was bound to her side. "Clarissa, please, you're in the presence of a princess!" Sebastian gestured to the playpen of human bones beside his own throne, where Lilith was happily playing with her favorite stuffed puppy.

"Master," Laramie said impatiently. "If you're not going to get a job, then at least end this hiatus we've been stuck in for the past week. Asmodeus is expecting the rent in a few days, and we have nothing to give him."

"Fine. We raid the New York Institute next."

Clary's eyes widened, and a muffled scream escaped her throat.

"Clarissa, no shrieking indoors," Sebastian scolded.

Clary spat out the gag and snarled, "Jace and the others will stop you! You don't stand a chance! All they have to do is—"

"What? Believe in themselves?" Sebastian cackled. "Amusing, really, Clarissa dear. Amatis!"

Silent as a shadow, Amatis emerged from behind Sebastian's throne. "Master."

He stifled a scream of shock and turned around in his throne. "A-Amatis, we invade London next. Start preparations."

"I thought we said New York?" Laramie piped up.

"I've changed my mind. Don't question me, Larry," Sebastian snapped.

"My name is not Larry."

"Whatever. Amatis, go."

"Yes, Master."

"And as for you," Sebastian turned to Lilith, who looked up from her stuffed toy to smile at her father. "It's naptime. Aren't you tired yet?"

She yawned.

"Of course you are. Come on, up." Sebastian scooped her into his arms. "Larry, do me a favor and carry Clarissa dear to my chambers, will you?"

Laramie shoved his abacus under his arm and sighed. "Yes, Master."

"Come, little princess." Sebastian crooned. "To bed."

"Don't you touch me, you creepy-ass— _hey!_ Put me down!"

Laramie grunted, "This would be easier for both of us if you didn't struggle— _ow!_ She kicked me!"

"Yes, she's fiery like that." Sebastian said nonchalantly. "Looks like I'm going to have to teach you some manners later tonight, Clarissa."

"Come near me and I _swear_ I will rip you a new—"

"Ah-ah," Sebastian tutted. "No swearing in front of the princess."

"—butthole."

"How crude."

"Crude? I'll show you crude, you big—"

"Larry, take her away. She'll upset Lily with all that shrieking."

Laramie heaved Clary into his arms and carried her off kicking and screaming. Sebastian rolled his eyes and let out an exasperated sigh. "Hopefully one day she'll learn, Lily."

Lilith stared at him with a blank expression on her face, rosy cheeks quickly inflating and deflating as she sucked her thumb. Sebastian's chest twinged. _How could such an innocent little lamb possibly have come from me and my sinful acts of lechery?_ He grazed her cheek with the crook of his finger. Lilith made a delighted sound and reached for him with both arms; they were short and chubby, like little sausages.

"I should take you to meet your grandmother Lilith someday," Sebastian mused. "I'm sure she'd simply adore you. Wouldn't you like that, Lily?"

Lilith blinked, and then broke into a gummy grin. "Ahh!"

"Yes, of course you would." Sebastian smoothed her fringe of pale hair. "Soon, Lily. Hush now. Go to sleep."

"Ah?"

"Ah," Sebastian echoed. "And soon you'll be talking. I suppose I shouldn't let you spend too much time around Aunt Clarissa; knowing her, your first word will probably be something along the lines of 'Shitbastian'."

"Shi-bastan!"

Sebastian's eyes widened. "Oh no."

"Shi-bastan!"

"No, Lily. Daddy. Say 'Daddy'!"

Lilith blinked. "Da…"

"Yes," Sebastian smiled. "Yes, that's it. You can do it, flower. Go on. Daddy."

"Da...da…"

"Daddy! Say Daddy!"

"Shi-bastan!"

Sebastian's jaw clenched. "Fuck."

Lilith clapped her hands. "Fu—"

"Don't you _dare,"_ Sebastian hissed. As if sensing her father's displeasure, Lilith quieted. Sebastian scowled. "You think you're real cute, don't you?"

Lilith giggled.

"You're not cute."

She reached out and touched his nose. Sebastian sucked in a sharp breath as his heart melted. "Cursed child. You've inherited all my charm."

She placed her tiny hand over his heart. "Da-dee."

Sebastian let out a very un-lordlike squeak.

"Da-dee!"

"I love you. You know that?" Sebastian brought his daughter close and pressed a kiss to her soft hair. "You might just be the best thing that's ever happened to me."

Lilith rested her head on his chest. "Da-dee."

He brought her small hand up to his lips and kissed it. "That's right. Daddy's got you."

Lilith yawned. "Shi-bastan."

He chuckled. "You're not going to grow out of that anytime soon, are you?"

She smacked her lips and her eyes fluttered closed. Sebastian adjusted the babe in his arms and started down the hallway, making sure to keep his footsteps quiet.


	8. Part 8

**Kind of a short one this time. No Lilith in this part, just a little Clary and Sebastian bantering. I wasn't feeling too inspired to work on this today, but I felt bad for** **keeping you guys waiting and decided to post something anyways.**

 **Lily will be back next chapter, I promise!**

"Hello, Clarissa."

Clary sat up on the bed with fear in her eyes. Sebastian shut the door and locked it, not bothering to hide the gleeful grin on his face. He started towards her, painfully slowly.

"Stay away from me, you freak!" Clary started kicking her legs, scooting over to the other side of the bed as her brother grew nearer.

"Calm down, Clarissa." Sebastian tutted. "I'm not going to hurt you."

"Sorry if I have a hard time believing that," Clary said monotonously.

"Clary, Clary, Clary," he sighed. "Where _do_ you get these ideas? Why would I ever want to hurt my baby sister?"

"Because you've got some sick, incestous obsession with me, freakshow."

Sebastian gazed down at Clary, tied up and vulnerable on his bed, and frowned. "I'll untie you," he said. "But you have to promise not to run away."

Clary laughed. "The day I stop fighting you will be the day that the Lions win the Superbowl."

Her brother tilted his head. "What?"

Clary rolled her eyes. "Of course you wouldn't know. Do you not know anything about modern society?"

"Not really. Did you forget? I grew up in a rural manor in Idris, Clarissa." He paused. "What is this 'Superbowl' thing, anyways?"

"Football championship."

"Football?" Sebastian rubbed his chin. "Ah. That mundane sport with the black-and-white ball, right?"

"Not in America, buddy. That's called soccer."

"And football is something else here?"

"Yeah, it's-" Clary's eyes narrowed. "Are you really making small talk with me right now?"

Sebastian shrugged. "I suppose I am."

"Well stop it, it's weird."

"Why is it weird for siblings to talk with each other?" Sebastian slid onto the bed and put his arms behind his head in a picture of leisure. "I just want to get to know my sister a little better."

"Well that's just a damn shame, because I don't want to get to know you."

"Why not?"

Clary glared at him. "Why? I'll tell you why." She hissed, "You're a murderer. A demon thing."

Sebastian placed his hand over his heart. "You wound me, dear sister." He crept towards her on all fours, like a predator stalking its prey.

Clary edged away from him. "I'll wound you for reals if you don't get away from me, you fucking psycho!"

"Come here, little sister," Sebastian purred, wrapping one arm around her middle. "Let's _snuggle."_

"Ew, ew, ew, stop touching me! You're gonna give me diseases!" Clary gasped. "Demon pox. You're gonna give me _demon pox!_ Oh Raziel, help me!"

Sebastian scowled. "I'm not going to give you demon pox, Clarissa."

"Oh Raziel, Raziel, please help me!" Clary wailed. "Send a bolt of lightning into Edom and smite this foul beast!"

"Clarissa-"

"Quickly, before he infects me!"

Sebastian huffed and pushed her away. "I can't give you pox. I'm not _full_ demon."

Clary smirked. "Demon pox, oh demon pox-"

"Clary, I swear, if you start singing that-"

"Just how is it acquired? One must go down to the bad part of town-"

"Your boyfriend _must_ be a Herondale-"

"-until one is very tired!"

"Shut up or I'll duct tape your mouth."

Clary stopped singing, but the silly grin never left her face. Sebastian growled at her. "You and Lilith have both driven me past the point of exhaustion. Goodnight, sister. I'll see you in the morning." He pushed off of the bed and skulked out of the room, slamming the door behind him.


	9. Part 9

**Part 9 - In Which Sebastian Introduces Endarkened Scout Cookies**

* * *

"Explain this to me, Amatis."

Amatis cleared her throat and set the box at Sebastian's feet. "They're cookies, my Lord. Laramie thinks it a good idea to give them out in exchange for money. Asmodeus is expecting the rent this month, and we have nothing to give him."

Sebastian turned his cold black gaze onto Laramie. "So, my faithful accountant's brilliant solution is to sell cheap baked goods to the mundanes?"

Laramie looked unimpressed. "My Lord, it's been nearly two weeks since we last talked, and you've made no move to attack another institute _or_ find a job. This is our last resort."

Sebastian growled. "I refuse to subject myself to such a humiliating form of manual labor."

"Then you've sentenced us to homelessness."

Sebastian grinned. "No I haven't. I said _I_ won't do it. _You_ will." He bounced a happy Lilith in his lap, rubbing his chin thoughtfully. "These cookies-what kind are they?"

"Thin mints," Laramie hissed through gritted teeth. "American mundanes adore them."

"That must be why they're all so grossly overweight," Sebastian said. "Very well, Mr. Hollyberry. Amatis. You are both dismissed. Take that cheap chocolate-covered cardboard out of my dimension and feed it to the mundanes. I expect a grand sum of 500 mundane dollars by the end of the day."

"Sir, according to my calculations, if we're selling each of these boxes for five dollars, we'd have to sell 100 boxes in only three hours."

"And?"

"And, that is physically impossible. If we calculate the time it would take for us to cover one block, assuming that we're selling in New York, and taking into account the probability of each residence to buy one box-"

"Oh for the love of Lilith, quit that yapping and get out." Sebastian rubbed his temples. "You're giving me a headache, Hollyberry."

Amatis unsheathed her blade and pointed it at the accountant's throat. "How dare you bring harm to my Lord Sebastian," she hissed. "Stop it immediately!"

"Amatis," Sebastian said tiredly. "Go fetch Lilith her bottle, would you?"

"Oh, as you wish, my Lord!" Amatis quickly sheathed her blade and scuttled out of the room, like a cockroach fleeing from a sudden bright light.

Laramie's emotionless brown eyes settled on Sebastian. "Shall I ask Amatis to organize patrols, my Lord?"

"Yes," Sebastian decided. "You will all start bright and early tomorrow morning. I will have a grand total of 5,000 American dollars by the time you return. Is that clear?"

Laramie let out an exasperated breath. "Crystal."

"Good." Sebastian eyed Lilith's dirty onesie with distaste. "My daughter has been wearing the same article of clothing for the past three weeks. Where would I purchase something else for her to wear?"

"My Lord, I am a 24 year-old accountant from Chicago. Do I _look_ like I would know where to buy baby clothes?" Laramie said irritably.

Sebastian sniffed. "I thought drinking from the Cup was supposed to make you all respect me."

"Respect you?" Laramie rolled his eyes. "No. Fear is a better word for it. Even though, I don't feel much of that, either."

"That's because you're an accountant and you have no soul," Sebastian said. "And that's coming from _me,_ Hollyberry. Valentine's neglected demon son. You have some serious issues."

"You're not wrong, my Lord." Laramie picked up the box of thin-mints and briskly left the room. Upon the accountant's departure and Amatis' return with Lilith's bottle, Sebastian decided to pay his sister a visit in her temporary prison.

Clary was still asleep when he arrived, shushing a fussy Lilith as she reached for the bottle in his other hand. His sister was not a graceful sleeper; she was sprawled out messily in a tangle of covers, snoring with a large amount of hair pasted to her cheek with drool.

Sebastian sniffed. "You see that beautiful creature there, Lilith? That's your aunt Clarissa. Though soon, if things work out, she'll also be your mother." He beamed. "Won't that be nice?"

Lilith paused and looked up at him with something like confusion in her big black eyes.

A muscle in Sebastian's jaw twitched. "What? Stop looking at me like that."

She didn't.

Sebastian huffed. "Whatever. You're a baby, what do you know? Here, would you like Aunty to feed you your bottle, Lily?" He set her on the bed beside Clary's sleeping form. "Go on. Wake her up."

Lilith examined her prey for a spell before reaching out with a chubby arm and yanking on a fistful of Clary's red curls. The girl yelped and sat up; Lilith giggled deviantly.

"Ow! Jonathan, what the hell?"

"Language, little sister," Sebastian crooned. "You're in the presence of a princess. Do try to remember, or I might have to _punish_ you."

Clary curled her lip. "You're gross. What do you want, freak show?"

"Lily wants you to feed her her bottle," Sebastian replied coolly. "You wouldn't want to disappoint her, would you?"

Clary made a face, wrinkling her nose and squinting her eyes. "By the Angel-but it's so _early!"_

"It's eight 'o' clock in the evening, Clarissa."

"Your point?"

"The princess demands her bottle and you will feed it to her, or face the dire consequences."

Lilith let out a gleeful laugh, clapped her hands, and rolled onto her back. She then proceeded to reach for her foot and stick it into her gummy mouth. Clary raised an eyebrow at her brother. "Oh yes, she's absolutely _terrifying._ What's she gonna do? Suck her thumb and give me the chair?"

Sebastian thrust the bottle into Clary's hands. "Just feed her the damn bottle, you stubborn woman."

"Language, big brother," Clary said, mocking her brother's posh accent. "You know, your accent sounds totally fake. I bet you actually grew up in Kentucky or something." She gathered Lilith up into her arms and stuck the bottle's teat into her mouth.

Sebastian huffed. "My accent is not fake."

"It's totally just for show," Clary insisted. "You're actually a hillbilly, aren't you? You're some kind of seriously troubled Cletus the Slack-Jawed Yokel!"

Sebastian made a face. "Who?"

"Nevermind," Clary sighed. "He married his sister too. Or his cousin. Or his mother. It's not really clear."

"I think we'd get along," Sebastian decided.

"Of course you think that." Clary scowled at him. "But seriously. Everyone knows you just use that dumb accent to pick up girls."

"Oh yes, you've caught me red-handed." He waggled his eyebrows. "Howdy."

Clary choked.


End file.
